1. Field of the Invention
This invention relates in general to wrenches, and in particular to an open end wrench that provides ratcheting action.
2. Description of the Prior Art
In a conventional open end wrench, a rigid jaw is joined to a shank. The jaws have parallel faces which slide over the sides of the nut. After each stroke, the user must remove the wrench from the nut and reposition it on the nut. Typically the nut is hexagonal, with a point or corner every 60 degrees. If an obstruction prevents repositioning a full 60 degrees, the user must also flip the wrench over with each stroke. This makes using such a wrench timeconsuming. Also, because of the necessary clearances between the sides of the nut and the two parallel drive surfaces, the actual contacting drive points are on the corners of the nut. This tends to round the corners, particularly when high torque is required.
A number of patents have issued disclosing open end wrenches that will ratchet. That is, the user is able to reposition the wrench on the nut for another stroke without having to completely remove the wrench from the nut. The designs have various deficiencies. Many of them drive only on the corners of the nut, tending to cause the nut to round at the corners. Of the fixed jaw type, each stroke must be 60 degrees from the preceding stroke. That is, the user must ratchet the wrench from one corner to the next corner of the nut. An intermediate position is not available. Also, the fixed jaw types require that the wrench be pulled away from the nut with each repositioning stroke. The next position is not self-seeking.
A wrench that is self seeking would have the characteristic of ratcheting from one driving position to the next while being held in contact with the nut. This self seeking characteristic would be due entirely to the design of the various surfaces, faces, points and angles of the wrench in relation to the nut to be turned, and would not require special positioning of the wrench by the user.